The present invention relates to a method of stereoselectively hydrogenating a ketone that is particularly useful as an intermediate for a CCR2 antagonist.
CCR2 is a chemokine receptor that is expressed on a cell surface of monocycles and some other blood leukocytes. CCR2 binds to the monocyte chemotactic protein MCP-1, and other CC chemokines, which are produced at sites of inflammation and infection. Recruitment of monocytes to inflammatory sites by MCP-1/CCR2 interactions has been implicated in driving the pathogenesis of a number of diseases including multiple inflammatory disorders including rheumatoid arthritis, atherosclerosis, multiple sclerosis, bronchiolitis obliterans syndrome, asthma, allergic rhinitis, eczema, atopic dermatitis, kidney disease, alveolitis, nephritis, liver cirrhosis, congestive heart failure, viral meningitis, cerebral infarction, neuropathy, Kawasaki disease, Alzheimer's disease, stroke, acute nerve injury, HIV infection, AIDS, autoimmune diseases, cancer, sepsis, retinosis, inflammatory bowel disease, transplant arteriosclerosis, idiopathic pulmonary fibrosis, psoriasis, HIV-associated dementia, lupus, erthematosis, hepatitis, pancreatitis, Crohn's disease, endometriosis, metabolic syndrome, and diabetes.
A number of compounds in the art described as CCR2 antagonists contain a chiral hydroxyethylene group that links two piperidinyl groups. For example, US 2008/0318990 discloses CCR2 modulators that contain the following 1S enantiomeric fragment:

It would be desirable to discover a new way to prepare these chiral molecules.